This is the interface's code(1 tried to save it as Unicode and Big Endian Unicode but nothing),1 save it as .xml.
code:
<Interfaces xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
        <Window Id="WndTest" Version="1">
            <Attributes>
                <Caption>Test Window</Caption>
            </Attributes>
            <TitleBar>
                <Title><Text>Hello!</Text></Title>
            </TitleBar>
            <Position Width="180" Height="75"/>
            <DialogTmpl/>
            <Controls>
                <Control xsi:type="StaticControl" Id="LblTop">
                    <Position Left="10" Top="10" Width="150"/>
                    <Caption>Hello world!</Caption>
                </Control>
                <Control xsi:type="ButtonControl" Id="BtnClose">
                    <Position Left="112" Top="25" Width="50"/>
                    <Caption>Close</Caption>
                </Control>
            </Controls>
        </Window>
    </Interfaces>
And this is the script:
code:
function OnEvent_Initialize(MessengerStart)
{
}
function OnEvent_Uninitialize(MessengerExit)
{
}
function OnEvent_Signin(Email) {
WindowName = MsgPlus.CreateWnd("InterfaceTest.xml", "WindowName");
}
Both are in the folder "WindowTest",the script is on,and when 1 access to msn,a window should be displayed..but nothing 
 
Did 1 make some errors in the code?Please helpT_T